I have a Tab 2 7.0, and I have the same problem.
My device detects its as 7cds + comneon Suspend and failed to install the drivers.

I've Kies installed but no luck
Switched USB port but result is same
switched PC but same
tried my friend's tab (same like mine) with settings USB->Modem to see weather there is problem with my USB but again no drivers.... i. e. no probs with my tab
Tried Your method but i don't have the "log via UART" instide I have "log via USB" which upon selecting gives me an error ""LOG PATH SET FAIL".
and then on selecting Modem on Diag menu gives me the same responce...

note: I dont have the DM+MODEM+ADB but only modem or PDA option... I guess it said to be "mux menu" for us.. correct me if I am wrong

Reflash with latest firmware and try again or try unlock it by microUART cable.

Thanks man. tried that and every other possible way. still the same issue. and also if I let the screen to lock automatically, the phone freezes
you know, this is the third phone I'm missing for mysterious reasons like this! I'm not a noob really but I'm thinking to avoid flashing and customizing my next devices!

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